System for making a conductive circuit on a substantially non-conductive substrate

ABSTRACT

A method for forming a conductive circuit on a substantially non-conductive substrate includes indenting a major surface of a substrate with a plurality of features, plating the major surface and the indentations formed with a conductive layer, and removing a portion of the conductive layer leaving at least one of the plurality of the indentations filled with conductive material separated from at least one other of the plurality of the indentations filled with conductive material separated by non-conductive material. An electrical device formed includes a sheet of insulative material having grooves therein. The sheet of insulative material has a first planar surface, and a second planar surface. A conductive material is positioned within the grooves. The conductive material within the grooves forms electrical traces in the electrical device. The conductive material within the grooves fills the groove and includes a surface coplanar with at least one of the first planar surface or the second planar surface. Other electrical devises can be formed using multiple sheets formed with electrical traces.

This application is a Divisional of U.S. application Ser. No. 10/612,705filed Jun. 30, 2003, which is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention is related to printed circuit boards. Morespecifically, the present invention relates to a method and apparatusmethod and apparatus for forming printed circuit boards using imprintingand grinding.

BACKGROUND OF THE INVENTION

A printed circuit board (“PCB”) is a multi-layer plastic board thatincludes printed circuits on one or more layers of insulative material.A printed circuit is a pattern of conductors that corresponds to thewiring of an electronic circuit formed on one or more layers ofinsulative material. The printed circuit board includes electricaltraces that are routed on the various layers of the PCB. PCBs alsoinclude vias which are solid electrical paths connecting one layer toanother layer. A via can be used to connect a trace on one layer of aPCB to another trace on another layer of the PCB. A PCB also includesother layers of metallization for ground planes, power planes orreference voltage planes.

One conventional way to make a PCB is to start with a sheet or strip ofdielectric coated with a conductive metal such as copper. Using variousdrilling, plating, lithographic and metal etching steps a pattern isthen formed leaving metal where traces are desired. The traces are ontop of the sheet or strip of dielectric. One sheet forms one layer ofthe PCB.

Another conventional way to make a PCB is to start with a sheet or stripof non-conductive plastic or ceramic, deposit ink in a pattern thatforms the conductive traces, sinter the ink to form metal traces. Thesheet or strip of non-conductive plastic or ceramic is sometimesreferred to as a manufacturing panel. Fiducial markings or coupons areplaced on the manufacturing panels. A PCB can have several layers oftraces. Five or six layers is common for a multi-layer PCB. Each layeris formed on a manufacturing panel and then the various layers areregistered with the fiducial markings or coupons and bonded together.The manufacturing panels form a laminate that includes a number ofindividual PCBs. The laminate formed is then further processed. Vias orpaths from one layer to another layer within the PCB are formed bydrilling through the PCB to hit various pads on each of the layers. Thepads are generally large enough to account for any inaccuraciesassociated with routing design or misregistration between the layers ofthe PCB. A PCB may also include various planes for power, groundreference or another voltage reference. As a result, each PCB requiressubstantial routing of signal lines and power-supply capability. Designchanges are difficult to make. Accounting for inaccuracies, such asmaking large inner pads for a via, limits the density of the signalcarrying lines and makes routing more difficult. Furthermore, theresulting PCB typically has stub traces that may result in undesirableelectrical qualities. For example, such stubs vary the impedence and mayresult in crosstalk between signal lines. Another aspect of current PCBsis that each plate carries a single layer of traces. Once the furtherprocessing of laminate formed is complete, the manufacturing panel iscut or singulated to form individual printed circuit boards.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is pointed out with particularity in the appended claims.However, a more complete understanding of the present invention may bederived by referring to the detailed description when considered inconnection with the figures, wherein like reference numbers refer tosimilar items throughout the figures and:

FIG. 1 is a top view of a printed circuit board, according to anembodiment of the invention.

FIG. 2 is a side view of a panel of material passing through a rollermechanism to indent the panel of the material, according to anembodiment of this invention.

FIG. 3 is a side view of a panel of material after plating one of themajor surfaces of an indented panel with a conductive material,according to an embodiment of this invention.

FIG. 4 is a side view of a panel of material after plating two of themajor surfaces of an indented panel with a conductive material,according to an embodiment of this invention.

FIG. 5 is a side view of a grinder mechanism removing at least a portionof the plated material from one surface of the panel, according to anembodiment of this invention.

FIG. 6 is a perspective view of a roller carrying a plate, according toan embodiment of this invention.

FIG. 7 is a front view of a roller that indents a panel of material anda load roller, according to an embodiment of this invention.

FIG. 8 is a cross-sectional side view of a portion of a panel ofmaterial after the panel of material has been indented, according to anembodiment of this invention.

FIG. 9 is a cross-sectional side view of a portion of an indented panelof material after the panel of material has been plated, according to anembodiment of this invention.

FIG. 10 is a cross-sectional side view of a portion of an indented panelof material after a portion of the plated material has been removed,according to an embodiment of this invention.

FIG. 11 is a cross-sectional side view of several panels joined to forma multi-layer electrical device, according to an embodiment of thisinvention.

FIG. 12 is a flow diagram showing a method of forming a conductivecircuit on a non-conductive substrate or panel, according to anembodiment of this invention.

FIG. 13 is a flow diagram showing another method of forming a conductivecircuit on a non-conductive substrate or panel, according to anembodiment of this invention.

FIG. 14 is a top view of a panel and an indenting system including a setof rollers for forming indented features on the panel, according to anembodiment of this invention.

FIG. 15 is a front view of an indenting system including a first set ofrollers and a second set of rollers for forming indented features ongrooves on two sides of a panel, according to an embodiment of thisinvention.

FIG. 16 is a side view of a panel of material passing through a set ofrollers to indent one side of the material, according to an embodimentof this invention.

FIG. 17 is a side view of a grinder mechanism for removing at least aportion of the plated material from two major surfaces of the panelsubstantially simultaneously, according to an embodiment of thisinvention.

FIG. 18 is a side view of a grinder mechanism for removing at least aportion of the plated material from two major surfaces of the panelsubstantially simultaneously, according to an embodiment of thisinvention.

FIG. 19 is a schematic view of a system for forming printed circuitboards, according to an embodiment of this invention.

FIG. 20 is a top view of a wafer, according to an embodiment of thisinvention.

FIG. 21 is a top view of a die within a package, according to anembodiment of this invention.

The description set out herein illustrates the various embodiments ofthe invention and such description is not intended to be construed aslimiting in any manner.

DETAILED DESCRIPTION

In the following detailed description of the preferred embodiments,reference is made to the accompanying drawings that form a part hereof,and in which are shown by way of illustrating specific embodiments inwhich the invention can be practiced. The embodiments illustrated aredescribed in sufficient detail to enable those skilled in the art topractice the teachings disclosed herein. Other embodiments can beutilized and derived therefrom, such that structural and logicalsubstitutions and changes can be made without departing from the scopeof present inventions. The following detailed description, therefore, isnot to be taken in a limiting sense, and the scope of variousembodiments of the invention is defined only by the appended claims,along with the full range of equivalents to which such claims areentitled.

FIG. 1 is a top view of a printed circuit board 100, according to anembodiment of the invention. The printed circuit board (“PCB”) 100 is amulti-layer plastic board that includes patterns of printed circuits onone or more layers of insulated material. The patterns of conductorscorrespond to wiring of an electronic circuit formed on one or more ofthe layers of the printed circuit board 100. The printed circuit board100 also includes electrical traces 110. The electrical traces 110 canbe found on an exterior surface 120 of a printed circuit board 100 andalso can be found on the various layers within the printed circuit board100. Printed circuit boards also include through holes (not shown inFIG. 1 but shown in FIGS. 10- 11) which are used to interconnect traceson various layers of the printed circuit board 100. The printed circuitboard can also include planes of metallized materials such as groundplanes, power planes, or voltage reference planes (not shown in FIG. 1).Through holes can also be used to interconnect like planes in theprinted circuit board 100. A through hole can either be a plated throughhole which is essentially a hollow conductor formed within the printedcircuit board 100 for interconnecting conductors or layers of a printedcircuit board, or it can be a via which is a solid conductor used tointerconnect layers of the printed circuit board 100.

The printed circuit board 100 is also populated with various components130, 132, 134, 136, 138. The components 130, 132, 134, 136, 138 caneither be discreet components or semiconductor chips which includethousands of transistors. The components 130, 132, 134, 136, 138 can useany number of technologies to connect to the exterior surface 120 of thecircuit board or to the printed circuit board 100. For example, pins maybe inserted into plated through holes or pins may be extended throughthe printed circuit board 100. An alternative technology is surfacemount technology where an electrical component, such as component 136,mounts to an array of pads on the exterior surface 120 of the printedcircuit board 100. For example, component 136 could be a ball grid arraypackage or device that has an array of balls or bumps that interact orare connected to a corresponding array of pads on the exterior surface120 of the printed circuit board 100. The printed circuit board 100 canalso include connectors for making external connections to otherelectrical or electronic devices.

As shown in FIG. 1, the printed circuit board 100 includes a first edgeconnector 140 and a second edge connector 142. As shown in FIG. 1 thereare external traces, such as electrical trace 110, on the externalsurface 120 of the printed circuit board 100 that connect to certain ofthe outputs associated with the first edge connector 140. Other tracesthat connect with the edge connectors 140, 142 will have traces internalto the printed circuit board 100.

Many of the electrical components which are used to populate the printedcircuit board 100 are expensive. For example, a central processing chip,that may cost hundreds or thousands of dollars, is generally mounted ona printed circuit board 100. As a result, it is desirable to test theintegrity of printed circuit boards, such as printed circuit board 100,before electrical components, such as electrical components 130, 132,134, 136, 138, are mounted onto the printed circuit board 100. It shouldbe noted that printed circuit boards are also called boards or circuitboards. Once populated many of the printed circuit boards are calledcards or adapters. Printed circuit boards are prevalent and are used incomputers and other devices. For example, printed circuit boards areused in computers and are referred to as motherboards, expansion boards,daughter cards, controller cards, network interface cards, or videoadapters or video graphics adapters. It should be noted that these arejust a small sample of the many different types of electronic devicesthat are based upon a printed circuit board, such as the one shown inFIG. 1.

FIG. 2 is a side view of a panel 210 of material passing through aroller mechanism 220 to indent the panel 210 of the material, accordingto an embodiment of this invention. The roller mechanism includes afirst indenting roller 221 and a second indenting roller 222. The rollermechanism 220 also includes load rollers 224, 225, 226, 227. The loadrollers 224, 225, 226, 227 apply opposing loads, depicted by arrows 234,235, 236, 237, on the panel 210 to flatten the panel 210 in and aroundthe area of the roller mechanism 220. For example, load roller 224opposes or is positioned directly, or nearly directly, opposite fromload roller 225. The force produced by load roller 224 is load 234 whichis directly opposite the load 235 produced by load roller 225.Similarly, load roller 226 is positioned opposite load roller 227. Loadroller 226 produces load 236 which directly opposes the load 237produced by the load roller 227. The various loads 234, 235, 236, 237 aswell as loads produced by the first indenting roller 221 and the secondindenting roller 222 flatten the panel of material 210 in the area ofthe roller mechanism 220. The panel of material 210 is a non-insulatedmaterial such as ABF plastic, a thermoplastic, or any other type ofthermoset plastic. The panel of material 210, after processing whichwill be discussed below, becomes one layer in a printed circuit board.It should be also noted that some circuit boards may have a single layerso another option is that the panel 210 may become a single layer in aprinted circuit board. The first indenting roller 221 and the secondindenting roller 222 are provided with pattern surfaces 241 and 242,respectively.

As the first indenting roller 221 roles and places a load on a majorsurface 211 of the panel of material 210, the pattern surface 241 of thefirst indenting roller 222 forms indentations within the major surfaceof the panel 211. Similarly, as the second indenting roller 222 rolls orplaces a load on a second major surface 212 of the panel of material210, the pattern surface 242 produces indentations and patterns in thesecond major surface 212 of the panel of material 210. It should benoted that indentations can produce all sorts of features includingopenings that pass through the panel of material 210 from the firstmajor surface 211 to the second major surface 212. In other words, thefeatures on the surface 241 of the first indenting roller 221 and thefeatures on the surface 242 of the second indenting roller 222 caninclude channels or pathways, paths, and through holes. It should benoted that the first indenting roller 221 and the second indentingroller 222 are indexed with respect to each other so that as theindentations are made in the first major surface 211 and the secondmajor surface 212 of the panel of material 210, the features will beregistered with one another as patterns of traces, through holes andpads are registered from layer to layer within a printed circuit board,such as printed circuit board 100 shown in FIG. 1.

After the panel of material 210 and specifically the first major surface211 and the second major surface 212 of the panel have been indentedwith the features from the surface 241 of the first indenting roller 221and the features associated with the surface 242 of the second indentingroller 222, the panel of material 210 is plated with an electricallyconductive material.

FIG. 3 is a side view of a panel of material 210 after plating one ofthe major surfaces 211 of the indented panel 210 with a conductivematerial 311, according to an embodiment of this invention. Althoughplating is mentioned as one way of placing conductive material 311 on tothe first major surface 211 of the panel of material 210, there are manyother ways to deposit conductive material 311 on to the first majorsurface 211 of the panel of material 210. For example, in addition toplating, the panel 210 could be placed in a chamber and conductivematerial 311 could be sputtered or placed thereon by chemical vapordeposition. It is contemplated that any form of depositing a conductivematerial 311 on to the surface 211 of the panel of material 210 iswithin the scope of this invention. Furthermore, the panel of material210 is not necessarily of a specific size. In fact, the panel ofmaterial 210 could be part of a continuous role of material thateventually becomes a layer, or one of a number of layers, in a printedcircuit board such as the one shown in FIG. 1. The panel of material 210could also be called a substrate on which the electrical traces, pads,and through holes are formed.

FIG. 4 is a side view of the panel of material 210 after depositingconductive material on the first major surface 211 and the second majorsurface 212 of the indented panel 210, according to an embodiment ofthis invention. As shown in FIG. 4, the first major surface 211 has aconductive layer 311 placed thereon, and the second major surface 212has a second layer of conductive material 312 deposited thereon. Thedeposited conductive material surfaces 311 and 312 fill the indentationsor features which are produced by the surfaces 241 and 242 of the firstindenting roller 221 and the second indenting roller 222, respectively(as shown in FIG. 2).

FIG. 5 shows a side view of a grinder mechanism removing at least aportion of the plate for deposited conductive material 311 from thefirst major surface 211 of the panel of material 210, according to anembodiment of this invention. The panel of material 210 is placed on aflat, stiff plate, depicted by reference numeral 510. The flat, stiffplate 510 includes a flat, stiff surface 511. The grinding mechanism 500includes a grinder 520 which has a grinding surface 540. The grinder 520rotates with respect to the first major surface 211 of the panel ofmaterial 210 as it is passed over the flat, stiff plate 510. Thegrinding mechanism also includes a first load roller 524 and a secondload roller 526 positioned on either side of the grinder 520. The firstload roller 524 produces a load depicted by an arrow having a referencenumber 534. Similarly the second load roller 526 produces a loaddepicted by the arrow carrying a reference numeral 536. The flat, stiffplate produces forces which counter the loads 534 and 536. As shown inFIG. 5, a load 535 counter acts the load 534 while a load 537counteracts the load 536. The load rollers 526, 524 flatten the surfaceof the substrate or panel of material 210 as it is being ground or asthe portion of the conductive surface 311 is removed from the firstmajor surface 211 of the panel of material 210. By removing a portion ofthe conductive material 311, conductive material only remains in theindentations or various features formed in the indentations in the panelof material 210.

In some embodiments of the invention the grinding mechanism 500 is setat a level so that a portion of the electrically conductive material311, as well as a portion of the first major surface 211, are removed bythe grinder 520. This assures that the conductive material that remainsin the features or indentations within the panel of material 210 areelectrically isolated from one another or are separated bynon-conductive material. As mentioned previously, the panel of material210 is made of a non-conductive plastic, such as ABF plastic,thermoplastic or thermoset plastic. It should also be noted that whenboth sides of the panel of material 210 are indented, both sides aretreated as shown in FIG. 5. In other words, a portion of theelectrically conductive material 312 is removed from the second majorsurface 212 of the panel of material 210. Also, in some embodiments, thegrinding process or grinder 520 may be set to also remove a portion ofthe second major surface 212. As shown in FIG. 5, the second majorsurface 212 has already had the portion of the conductive layer 312removed. In other words, the second major surface 212 was alreadytreated in the panel of material 210 shown in FIG. 5.

FIG. 6 is a perspective view of an indenting roller 600 which carries aplate 610 having an intending surface 620, according to an embodiment ofthis invention. The roller 600 is a continuous roller which has a widththat roughly corresponds to the width of the panel of material 210.Roller 600 includes a plate 610. The plate 610 is removable from theroller 600. In other words, the plate 610 is interchangeable with otherplates that can be placed on the roller 600. The plate 610 includes asurface 620. The surface 620 includes features which are rolled into themajor surfaces of the panel of material 210 (shown in FIG. 2). Thefeatures result in indentations in the first major surface 211 or thesecond major surface 212 of the panel of material 210. The plate 610 isinterchangeable with other plates because as the roller 600 and theplate 610 roll over the panel of material 210 the features 620 on thesurface of the plate 610 eventually wear to the point where theindentations produced by the feature 620 are unacceptable.

A new plate 610 having the same pattern of feature 620 can then beplaced upon the roller 600 to continue the operation of forming printedcircuit boards such as printed circuit board 100, from the panel ofmaterial 210. A plate 610 is formed from a mold of a master surface. Amaster surface having features similar to the features 620 on plate 610is first formed and qualified. Once formed and qualified, a mold is thenformed of the plate or of the master. A plate 610 is formed having thefeature 620 by forming the plate from the mold. In some instances theoriginal master is referred to as the father, the mold from the masteror father is referred to as the mother and the plate that is formed fromthe mother is referred to as the son. Therefore as the plates, such asplate 610 wear, the plate 610 can be replaced with another son made fromthe mold or mother. Multiple mothers can be made from the master andmultiple sons can be made from each mold or mother. As a result, thereis very little wear on the master and the master will last for a longtime. It should be noted that the indentation process can also be doneon a single side of a panel of material 610. FIG. 7 shows such anarrangement.

FIG. 7 is a front view of a roller 700 having a plate 710, according toan embodiment of this invention. The plate 710 includes feature 720. Theplate 710 is removable and interchangeable so that it may be changed outwith respect to the roller 700. As shown in FIG. 7, the roller 700 isused to indent a panel of material 210 having a first major surface 211and a second major surface 212. Specifically, the roller 700 is beingused to indent the first major surface 211 of the panel of material 210.In the front of the roller 710 is a load roller 734. The load roller 734produces a localized load on the panel of material 210 in the area ofthe indenting roller 700. The load roller 734 flattens the panel ofmaterial 210 against a flat stiff plate 740 and specifically against asurface 741 of the flat stiff plate 740. The end result is that theroller 700 produces indentations on a single side associated with thefirst major surface 211 of the panel of material 210. The feature 720correspond to channels, through holes and pads associated with oneparticular layer of a printed circuit board in a finished printedcircuit board. The features formed in the first major surface 211 of thepanel of material 210 are filled with conductive material and thenground, as discussed with respect to FIGS. 2-5 above. The second majorsurface 212 of the panel of material 210 can be similarly treated,plated and ground so that the panel of material has two surfaces ofelectrical traces. Another option is to leave the panel 210 having asingle surface with indentations and traces and pads filled withconductive material.

FIGS. 8-10 are cross-sectional side views of a panel of material duringthe various stages of forming a layer or two layers of a printed circuitboard. FIG. 8 is a cross-sectional side view of a portion of a panel ofmaterial 210 after the panel has been indented, according to anembodiment of this invention. As shown in FIG. 8, the first majorsurface 211 has been indented with a channel 810 that corresponds to atrace in electrical circuit. The channel 810 occurs in the first majorsurface 211 of the panel of material 210. Also formed by the indentationprocess is a pad 812 and a through opening 814 and a pad 816. Pads 812and 816 correspond to the through opening 814. Pad 812 is positioned orin the first major surface 211 of the panel of material. Pad 816 is inthe second major surface 212 of the panel of material. The through hole814 extends from the first pad 812 to the second pad 814. The throughhole 814 extends through the panel of material. Another channel 818 isalso formed in the second major surface 212 of the panel of material. Itshould be noted that the channel 810 corresponds to a trace and thechannel 818 also corresponds to an electrical trace in a finishedprinted circuit board, such as the printed circuit board 100 shown inFIG. 1. The trace 810 is wider than the trace 818, since the trace 810occurs along the cross-sectional cut and the trace 818 is shorter sincethe cross-sectional cut through the panel of material 210 crosses theelectrical trace 818.

FIG. 9 shows the panel of material 210 after the first major surface 211and the second major surface 212 have had conductive material 311deposited on the first major surface 211 and conductive material 312deposited on the second major surface 212 of the panel of material,according to an embodiment of this invention. As mentioned above theconductive material 311, 312 can be deposited in any number of ways. Theend result is that the channels 810, 818 and the pads 812, 816 and thethrough hole 814 are all completely filled with conductive material 311,312. It should be noted that the electrically conductive material 311,312 is the same. Furthermore, it should be noted that the conductivematerial 311, 312 can be plated on to the pad of material, and in thatcase, the first major surface 211 and the second major surface 212 areplated or have electrically conductive material 311, 312 placed on bothsides of the panel of material simultaneously. If other processes areused the first major surface 211 may have to have their electricallyconductive material 311 deposited thereon in a first operation and thesecond major surface 212 of the panel of material 210 may have to haveelectrically conductive material 312 added in a separate operation.

FIG. 10 is a cross-sectional side view of the portion of the indentedpanel of material 210 after a portion of the electrically conductivematerial 311, 312 has been removed, according to an embodiment of thisinvention. The end result is that the indentations for traces 810, 818are now filled with electrically conductive material 311, 312 and areseparated from other traces and other electrical features of the panelby insulative material of the panel of material 210. Thus the channels810 and 818 result in electrical traces 1010 and 1018. Also formed is avia 1014 within the opening 814 in the panel of material 210 as well aspads 1012 and 1016 on each end of the via 1014. Pad 1012 is formed inthe indentation 812 and pad 1016 is formed in the indentation 816. Allelectrically conductive features are isolated from other features. Asmentioned previously, a portion of the electrically conductive material311, 312 can be removed in addition to a portion of the first majorsurface 211 and the second major surface 212 so as to assure that thefeatures formed are located within the various indentations 810, 818,812, 816. It is also worthy of note that the traces 1010, 1018 and thepads 1012, 1016 are flush with respect to the first major surface 211and the second major surface 212 of the panel of material. In otherwords, the electrical traces 1010, 1018 are not on top of the firstmajor surface 211 and the second major surface 212 of the panel ofmaterial 210. Similarly the pads 1012, 1016 are also not atop the firstmajor surface 211 and the second major surface 212 of the panel 210, butrather are flush with the first major surface 211 and the second majorsurface 212. It should be noted that features are formed on two surfacesof the panel of material 210 as shown in FIG. 10. Thus, a single panelof material or a single layer of material yields two layers ofelectrical traces or electrical features. As a result, a printed circuitboard having two layers of features is much thinner than conventionalprinted circuit boards since the panel of material 210 includes twolayers of electrical features. In conventional design, a print circuitboard having two layers of electrical features would require two panelsof material or two layers of insulated material. It should also be notedthat indentations can be made on a single surface and so a single layerof electrical features can be formed on just one side of a panel ofmaterial 210 to form a single surface printed circuit board.

An advantage of forming two layers of electrical features on a singlepanel of material 210 is that it is not necessary to join two layers toform the required printed circuit.

An electrical device includes a sheet of insulative material havingindentations or grooves 810, 812 therein. The sheet of insulativematerial has a first planar surface 211, and a second planar surface212. A conductive material 311 is positioned within the indentations orgrooves 810, 812. The conductive material within the indentations orgrooves forms electrical traces 1010, 1012 in the electrical device. Theconductive material 311 within the indentations or grooves 810, 812fills the groove and includes a surface coplanar with at least one ofthe first planar surface 211 or the second planar surface 212. In someembodiments, the first planar surface 211 of the sheet of the insulativematerial or panel of material 210 has indentations or grooves 810, 812therein, and the second planar surface 212 of the insulative materialhas indentations or grooves therein. The indentations or grooves 810,812 in the first planar surface 211 and the second planar surface 212 ofthe sheet of the insulative material 210 are filled with the conductivematerial. The conductive material 311, 312 within the grooves in thefirst planar surface 211 includes a surface coplanar with the firstplanar surface. The conductive material 312 within the grooves 816, 818in the second planar surface 212 also includes a surface coplanar withthe second planar surface.

The electrical device includes an exterior surface 211. The exteriorsurface 211 of the electrical device includes features that are flushwith the exterior surface 211 of the device. In some embodiments, thefeatures that are flush with the exterior surface 211 of the device arepads 1012. The exterior surface 211 is ground or formed by grinding.

The electrical device includes an exterior surface 211. The exteriorsurface 211 of the electrical device includes features that are flushwith the exterior surface 211 of the device. In some embodiments, thefeatures that are flush with the exterior surface 211 of the device arepads 1012. The exterior surface 211 is ground or formed by grinding.

FIG. 11 is a cross-sectional side-view of several panels of material1110, 1112, 1114 joined together to form a multi-layer electrical device1100, according to an embodiment of this invention. Multi-layerelectrical device 1100 includes six layers of electrical traces in thethree panels of material 1110, 1112, 1114. The electrical traces areformed in indentations or grooves 1130, 1131, 1132 associated with thefirst panel of material 1110, and in grooves 1140, 1141, 1142 orindentations formed in the second panel of material 1112. The firstpanel of material 1110 includes a first major surface 1120 and a secondmajor surface 1121. The second panel of material 1112 includes a firstmajor surface 1122 and a second major surface 1123. The third panel ofmaterial 1114 includes a first major surface 1124 and a second majorsurface 1125. All of the major surfaces 1120, 1121, 1122, 1123, 1124,1125 are planar surfaces or substantially planar surfaces having thegrooves or indentations therein.

The grooves or indentations are only numbered for two of the panels ofmaterial 1110, 1112. The grooves or indentations were not numbered forthe panel of material 1114 for the sake of clarity. The grooves orindentations associated with the first panel of material 1110, thesecond panel of material 1112, and the third panel of material 1114,have grooves or indentations such as grooves or indentations 1130, 1131,1132, 1140, 1141, 1142, 1143 that are filled with an electricallyconductive material 1150. The electrically conductive material 1150forms electrical traces in the first panel of material 1110, the secondpanel of material 1112, and the third panel of material 1114 as well asbetween the various panels of material 1112, 1114, 1110. As can be seenby electrical device 1100, its form can be much thinner than otherelectrical devices which have a layer of electrical traces on each layerwithin the electrical device.

As shown in FIG. 11, each layer of the electrical device whichcorresponds to a panel of material 1110, 1112, 1114 includes two layersof electrical devices or electrical traces. Further advantage of thismulti-layer electrical device 1100 shown in FIG. 11 is that certainimprecise processes are no longer necessary to form the printed circuitboard. For example, forming a via generally included forming a drillopening within the multi-layer device and hitting various pads invarious layers of the printed circuit board. As shown in FIG. 11, amulti-layer printed circuit board 1100 formed using the systems anddevices as well as the method described in the figures of thisapplication will no longer require drilling through several layers ofprinted circuit board. Another advantage of this invention is that thetraces can be more closely spaced and the traces can be made smallersince the various layers formed are merely placed together and thenbonded.

In some embodiments, the electrical device has a first sheet and asecond sheet of insulative material formed from a first panel ofmaterial 1110 and a second panel of material 1112. Both the first sheetand the second sheet of insulative material have a first planar surface1120, 1122 and a second planar surface 1121, 1123 with grooves orindentations 1130, 1131, 1132, 1140, 1141, 1142, 1143 therein that arefilled with a conductive material 1150. The conductive material 1150forms electrical traces in the first sheet of insulative material andthe second sheet of insulative material when the first sheet ofinsulative material is attached to the second sheet of insulativematerial. The two sheets, when attached, form a multi-layered electricaldevice 1110.

FIG. 12 is a flow diagram showing a method of forming a conductivecircuit on a non-conductive substrate or panel 1200, according to anembodiment of this invention. The method for forming a conductivecircuit on a substantially non-conductive substrate 1200 includesindenting a major surface of a substrate with a plurality of features1210, plating the major surface and the indentations formed with aconductive layer 1212, and removing a portion of the conductive layerleaving at least one of the plurality of the indentations filled withconductive material separated from at least one other of the pluralityof the indentations filled with conductive material separated bynon-conductive material 1214. The major surface of the substrate isindented with a roller. In some embodiments, the major surface of thesubstrate is indented with a plurality of indenting devices. Removing aportion of the conductive layer 1212 includes grinding a portion of theconductive layer 311 (shown in FIG. 5). A conductive circuit is formedon a substantially non-conductive substrate, according to the method setforth in this paragraph.

FIG. 13 is a flow diagram showing another method of forming a conductivecircuit on a non-conductive substrate or panel 1300, according to anembodiment of this invention. The method for forming a conductivecircuit on a substantially non-conductive substrate 1300 also includesindenting a first major surface of a first substrate with a firstplurality of features 1310, indenting a second major surface of a firstsubstrate with a second plurality of features 1312, plating the firstmajor surface and the indentations formed in the first major surfacewith a conductive layer 1314, and plating the second major surface andthe indentations formed in the second major surface with a conductivelayer 1316. The method 1300 further includes removing a portion of theconductive layer on the first major surface leaving at least one of theplurality of the indentations in the first major surface filled withconductive material separated from at least one other of the pluralityof the indentations in the first major surface filled with conductivematerial separated by non-conductive material 1318, and removing aportion of the conductive layer on the second major surface leaving atleast one of the plurality of the indentations in the second majorsurface filled with conductive material separated from at least oneother of the plurality of the indentations in the second major surfacefilled with conductive material separated by non-conductive material1320.

Once the panel has been formed with multiple layers, or once a panel isformed having two layers and that is what is desired for a finalproduct, the panel of material 210 will be sliced into individualprinted circuit boards such as printed circuit board 100 shown inFIG. 1. As mentioned previously, there are many types of printed circuitboards and FIG. 1 only shows one type of printed circuit board. Theinvention contemplates manufactured printed circuit boards for allapplications.

FIG. 14 is a top view of a panel of material 210 and an indenting system1400 including a set of rollers 1410 and a set of rollers 1420 forforming indented features on the panel of material 210, according to anembodiment of this invention. The first set of rollers 1410 includesindividual rollers 1411, 1412, 1413, 1414, 1415, and 1416. The secondset of rollers 1420 includes individual rollers 1421, 1422, 1423, 1424,and 1425. Each of the individual rollers 1411, 1412, 1413, 1414, 1415,1416, 1421, 1422, 1423, 1424, and 1425 have features thereon which areused to indent the panel of material 210 to form grooves which are laterfilled per the previous discussion with respect to FIGS. 1-13. Each ofthe individual rollers in the first set of rollers 1410 and the secondset of rollers 1421 need not be circular in cross-section. As shown inFIG. 14 the cross-sectional areas can be circular as depicted byreference numeral 1430 hexagonal as depicted by reference number 1432 oroctagonal as depicted by reference numeral 1434. These are not the onlytypes of cross-sectional areas that are contemplated. A roller havingany cross-section that will produce an indentation or groove in thepanel of material 210 is within the scope of this invention.

FIG. 15 is a front view of an indenting system 1500 including a firstset of rollers 1510 and a second set of rollers 1530 for formingindented features on grooves on two sides of a panel of material 210,according to an embodiment of this invention. The first set of rollers1510 includes individual rollers 1511, 1512, 1513, 1514, 1515, 1516,1517, 1518, 1519, 1520 and 1521. The second set of rollers 1530 includesindividual rollers 1531, 1532, 1533, 1534, 1535, 1536, 1537, 1538, 1539,1540 and 1541. The first set of rollers 1510 impact the first majorsurface 211 of the substrate of the panel of material 210. The secondset of rollers 1530 impacts and indents or forms grooves in the secondmajor surface 212 of the panel of material 210. Again the individualrollers or indenters need not have a circular cross-section but can havecross-sections of any type that will form indentations within the firstmajor surface 211 and the second major surface 212 of the panel ofmaterial 210.

FIG. 16 is a side view of a panel of material 210 passing through a setof rollers 1610 to indent one side of the panel of material 210,according to an embodiment of this invention. The set of rollers 1610includes an indenting roller 1620 having features on a surface 1621 ofthe roller used to form channels, indentations or grooves in the firstmajor surface 211 of the panel of material 210. The set of rollers 1610also includes a first load roller 1630 and a second load roller 1632.The first load roller 1630 and the second load roller 1632 produce loadsto flatten the panel of material 210 near or proximate the indentationroller 1620. The panel 210 is placed over a flat, stiff plate 510. Theflat, stiff plate 510 includes a flat, stiff surface 511 which producesforces counteracting the forces produced by the load rollers 1630, 1632.The force produced by the load rollers 1630 and 1632 are depicted byarrows carrying the reference numerals 1650 and 1652. The counteractingforces produced by the stiff, flat plate 510 are shown by arrowscarrying the reference numerals 1660 and 1662.

FIG. 17 is a side view of a grinder mechanism 1700 for removing at leasta portion of the plated material from the first major surface 211 andfrom the second major surface 212 of the panel of material substantiallysimultaneously 210, according to an embodiment of this invention. Thegrinding mechanism 1700 includes a first grinding wheel 1710 and asecond grinding wheel 1720. The first grinding wheel 1710 removesmaterial from the top surface associated with the first major surface211 and the second grinding wheel 1720 removes material associated withthe second major surface 212 of the panel of material 210. The grindingwheels 1710 and 1720 work substantially simultaneously to removematerial such as electrically conductive material that has been platedon the surfaces 211 and 212. The grinding mechanism 1700 also includes afirst pair of opposed load rollers 1730 and a second pair of opposedload rollers 1740 which flatten the panel of material 210 near the firstgrinding wheel 1710 and the second grinding wheel 1720.

FIG. 18 is a side view of a grinder mechanism 1800 for removing at leasta portion of the plated material from two major surfaces of the panel210 substantially simultaneously, according to an embodiment of thisinvention. The grinding mechanism 1800 includes a first set of aplurality of grinders 1810 and a second set of a plurality of grinders1820. The first set of the plurality of grinders 810 is used to removematerial from the first major surface 211 of the panel of material 210.The second set of grinding devices 1820 removes material associated withthe second major surface 212 of the panel of material 210.

FIG. 19 is a schematic view of a system 1900 for forming printed circuitboards, according to an embodiment of this invention. The systemincludes an indenter 1910, a plater or depositor of conductive material1912, and a removal tool 1914 for removing portions of conductivematerial from major surfaces of a substrate or panel of material 210(shown in FIG. 2).

Now, with respect to FIG. 19 and FIGS. 2-18, a system for making aconductive circuit on a substantially non-conductive substrate includesan indenter 1910 that forms a plurality of indentations on a first majorsurface 211 of the substrate 210, a plater that plates conductivematerial 311, 312 on the major surface 211, 212 of the substrate 210(shown in FIG. 2) and within the indentations formed in the majorsurface 211, 212 of the substrate 210, (shown in FIG. 2) and a removaltool or grinder 1914 that removes a portion of the conductive materialplated on the major surface of the substrate to leave conductivematerial within the indentations in the major surface of the substrate.The conductive material 311, 312 (shown in FIG. 3) within at least someof the plurality of indentations is separated from the conductivematerial within some of the other indentations by non-insulativematerial. The grinder 1914 removes a portion of the conductive material311, 312 (shown in FIG. 3) within the plurality of indentations. Thegrinder 1914 also removes a portion of the conductive material withinthe plurality of indentations to form a planar surface includingnon-conductive material and conductive material. The indenter 1910includes a plate having a negative of the indentations in the substrate.In some embodiments, the indenter 1910 is a roller. The roller includesan interchangeable plate having a negative of the indentations in thesubstrate. The indentations include at least one channel, at least onepad, or at least one via. In some embodiments, the indenter 1910includes a plurality of planar surfaces. The indenter 1910, in someembodiments, has multiple sides.

A system 1900 for making a conductive circuit on a substantiallynon-conductive substrate 1900 includes a first roller apparatus thatforms a plurality of indentations on a first major surface of thesubstrate 221 (shown in FIG. 2), and a second roller apparatus thatforms a plurality of indentations on a second major surface of thesubstrate 222 (shown in FIG. 2). The system for making a conductivecircuit on a substantially non-conductive substrate further includes aplater 1912 that plates conductive material on the first major surfaceof the substrate 211 (shown in FIG. 2) and on the second major surfaceof the substrate 212 (shown in FIG. 2) and within the indentationsformed in the first major surface of the substrate and in the secondmajor surface of the substrate 210 (shown in FIG. 2), and a grinderapparatus 1914 that removes a portion of the conductive material platedon the first major surface of the substrate leaving conductive materialwithin the indentations in the first major surface of the substrate, andremoves a portion of the conductive material plated on the second majorsurface of the substrate leaving conductive material within theindentations in the second major surface of the substrate, wherein theconductive material within at least some of the plurality ofindentations is separated from the conductive material within some ofthe other indentations by non-insulative material. In some embodiments,the grinder apparatus includes a plurality of grinders. In someembodiments of the invention, the first roller apparatus is comprised ofa plurality of rollers.

Although the invention has been described above using a printed circuitcard as an example of a substrate, it should be noted that the inventioncontemplates application to any type of substrate. A substrate includesa wafer and a die within a package. FIG. 20 is a top view of a wafer2000, according to an embodiment of this invention. The wafer 2000 shownhas markings thereon indicating the portions of the wafer that will beindividual dies or chips. In reality, the markings on the surface of thewafer 2000 are not present. FIG. 21 is a top view of a die 2100 within apackage 2110, according to an embodiment of this invention. The die 2100is one type of substrate that this invention includes and the package2110 is another type of substrate the invention includes.

The foregoing description of the specific embodiments reveals thegeneral nature of the invention sufficiently so that others can, byapplying current knowledge, readily modify and/or adapt it for variousapplications without departing from the generic concept, and thereforesuch adaptations and modifications are intended to be comprehendedwithin the meaning and range of equivalents of the disclosedembodiments.

It is to be understood that the phraseology or terminology employedherein is for the purpose of description and not of limitation.Accordingly, the invention is intended to embrace all such alternatives,modifications, equivalents and variations as fall within the spirit andbroad scope of the appended claims.

1. An electrical device comprising: a sheet of insulative materialhaving grooves therein, the sheet of insulative material including: afirst planar surface; and a second planar surface a conductive materialwithin the grooves, the conductive material forming electrical traces inthe electrical device.
 2. The electrical device of claim 1 wherein theconductive material within the grooves fills the groove and includes asurface coplanar with at least one of the first planar surface or thesecond planar surface.
 3. The electrical device of claim 1 wherein thefirst planar surface of the sheet of the insulative material has groovestherein, and wherein the second planar surface of the insulativematerial has grooves therein.
 4. The electrical device of claim 1wherein the first planar surface of the sheet of the insulative materialhas grooves therein that are filled with the conductive material, andwherein the second planar surface of the insulative material has groovestherein that are filled with the conductive material.
 5. The electricaldevice of claim 4 wherein the conductive material within the grooves onthe first planar surface fills the groove and includes a surfacecoplanar with the first planar surface, and wherein the conductivematerial within the grooves on the second planar surface fills thegroove and includes a surface coplanar with the second planar surface.6. The electrical device of claim 1 further comprising a second sheet ofinsulative material, the second sheet of insulative material including:a first planar surface; and a second planar surface a conductivematerial within the grooves of the second sheet of insulative material,the conductive material forming electrical traces in the electricaldevice, wherein the second sheet of insulative material is attached tothe first sheet of insulative material to form a multi-layeredelectrical device.
 7. The electrical device of claim 1 wherein one ofthe first planar surface or the second planar surface is an exteriorsurface of the electrical device, the exterior surface of the electricaldevice including features that are flush with the exterior surface ofthe device.
 8. The electrical device of claim 7 wherein the featuresthat are flush with the exterior surface of the device are pads.
 9. Theelectrical device of claim 7 wherein the exterior surface is ground. 10.A system for making a conductive circuit on a substantiallynon-conductive substrate, the system comprising: an indenter that formsa plurality of indentations on a major surface of the substrate; aplater that plates conductive material on the major surface of thesubstrate and within the indentations formed in the major surface of thesubstrate; and a grinder that removes a portion of the conductivematerial plated on the major surface of the substrate leaving conductivematerial within the indentations in the major surface of the substrate,wherein the conductive material within at least some of the plurality ofindentations is separated from the conductive material within some ofthe other indentations by non-insulative material.
 11. The systemaccording to claim 10 wherein the grinder removes a portion of theconductive material within the plurality of indentations.
 12. The systemaccording to claim 10 wherein the grinder removes a portion of theconductive material within the plurality of indentations and theconductive material over the non-conductive material between theindentations to form a planar surface including non-conductive materialand conductive material.
 13. The system according to claim 10 whereinthe indenter includes a plate having a negative of the indentations inthe substrate.
 14. The system of claim 10 wherein the indentationsinclude at least one channel.
 15. The system of claim 10 wherein theindentations include at least one pad.
 16. The system of claim 10wherein the indentations include at least one via.
 17. An electricaldevice comprising: a sheet of insulative material having indentationstherein, the sheet of insulative material including: a first planarsurface; and a second planar surface a conductive material within theindentations, the conductive material forming electrical traces in theelectrical device.
 18. The electrical device of claim 16 wherein theconductive material within the indentations fills the indentations andincludes a surface coplanar with at least one of the first planarsurface or the second planar surface.
 19. The electrical device of claim18 wherein the at least one of the first planar surface or the secondplanar surface includes an indentation that forms a via in theelectrical device.
 20. The electrical device of claim 16 wherein thefirst planar surface of the sheet of the insulative material hasindentations therein that are filled with the conductive material, andwherein the second planar surface of the insulative material hasindentations therein that are filled with the conductive material.